Mitsubishi Electric PFAV-P250VM-E Service Manual page 100

[ VIII Control ]
Fan operation on the Fresh Air Intake type units
When the return air dry temperature is 5°C [41°F] or below, units may be forced to operate in the heating mode to prevent
humidifier from freezing up and to prevent cold drafts.
The fan will stop when all refrigerant systems are in trouble and during the defrost cycle. Refer to the table below for how to
set the related switches and for the operation patterns.
Specification SW
Forced heating SW
operation/Fan 1-7
operation when
units are in trou-
ble
Fan operation SW
during defrost 3-4
cycle
1) The settings in the shaded areas indicate factory settings.
2) Turning on the fan during the defrost cycle will send cold air into the room, delay normal operation from being resumed, and
cause the room temperature to drastically drop. To avoid this, set SW3-4 to OFF.
3) The operating temperature (return air dry temperature) of the fan is 0°C [32°F] or above. If the fan is operated at the outside
temperature below 0°C [32°F], depending on the ambient air conditions, dew condensation may form on the panel surface.
Use caution so that dew drips will not damage the surrounding equipments.
2) SW2,SW3-2,SW3-9,SW3-10,SW4
Model System Capacity SW3-2 SW3-9 SW3-10
−
P300-F 50 OFF
− 100 ON
P600-F
No.1 100 ON
P900-F
No.2 50 OFF
(3) Address switches
How to set the indoor unit addresses depends on the system. Refer to the Outdoor Unit Installation Manual and other related
documents for how to set the addresses.
Each address consists of two digits.
(Example)
To set the address to "3," set the 1's digit to "3" and leave the 10's digit to "0."
To set the address to "25," set the 1's digit to "5" and the 10's digit to "2."
3. Switch functions <Remote controller>
(1) MA remote controller (PAR-21MAA)
MA remote controller does not have switches. Refer to the Operation Manual for how to make the function settings.
HWE10190
Operation
OFF
Forced heating op- Forced heating op-
eration is disabled. eration is enabled.
The fan will operate The fan will not op-
when the units are erate when the
in trouble. (The fan units are in trouble.
will stop when the
fan is in trouble or
when there is a
communication er-
ror.)
The fan will not op- The fan will operate
erate when the when the units are
units in all refriger- in the defrost cycle.
ant systems are in
the defrost cycle.
SW2
1 2 3 4 5 6
OFF ON
ON
OFF
1 2 3 4 5 6
OFF ON
ON
OFF
1 2 3 4 5 6
OFF OFF
ON
OFF
1 2 3 4 5 6
OFF OFF
ON
OFF
ON
When the return air dry temperature is 5°C [41°F] or
below, units are forced to operate in the heating
mode regardless of the mode setting to prevent
cold drafts.
The units will resume operation in the selected
mode when the return air dry temperature reaches
6°C[43°F].
Regardless of the outside air temperature, the fan
will not operate if there are any problems.
This switch is set to off to prevent the humidifier
from freezing up and to prevent cold drafts.
<Notes on capacity code and model settings>
SW4
If the capacity code or model setting has been incorrectly
1 2 3 4 5
set (e.g., when replacing the circuit board), both the indoor
and outdoor units need to be power reset.
1 2 3 4 5
1 2 3 4 5
1 2 3 4 5
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Notes
GB